The spikes actually are taken from the "speech bubble" in Photoshop's custom shapes. In my first submission, the word "talk" was inside a speech bubble, so what I actually did was that I transformed the speech bubble into the letter "t".

In my last entry, the spike is on both letters (t and f (f is also a t actually)) so that when you turn the logo upside down, it still looks the same. Get my idea?